Automatic gunnery-correcting device.



No. 865,247. PATENTED SEPT. 3, 1907.

. E. W. HUBBARD.

AUTOMATIC GUNNERY CORRECTING DEVICE.

APPLIOATION FILED AUG. 18. 1906.

BSHEETS-SHBET l.

arab,

Jly.

Dwniors Elnr W'Hubb Witnesses:

'hama C. mx/wc No. 865,247. PATENTED SEPT. 3, 1907. E. W. HUBBARD.

AUTOMATIC GUNNERY CORREOTING DEVICE.

APPLIOATION FILED AUG. 18. 190e.

s SHEETS-SHEET z.

No. 865,247. PATENTED SEPT. 3, 19C?. B. W. HUBBARD.

AUTOMATIC CUNNERY CCRRBCTINC DEVICE.

APPLICATION FILED 5116.18. 190C.

3 SHEETS-SHEET 3 AT MOSJZ lwe r Wjubbam;

MI/'m4,

CORRE ION POWDER ICLMER W. HUBBARD, OF THE UNITED STATES ARMY.

AUTOMATIC GUNNERY-CORRECTIN G- DEVICE.

Specification of Letters Patent.

Patented sept. 3, 1907.

Application tiled August 18,1906. lSerial No. 331,124.

vTo all ahorn it may concern:

Bc it known that l, Emma W. HUnBAno, a citizen of the United States ofAmerica, and a captain in the Artillery Corps of thc United States/'Armstationed at Fort Revere. Hull, in the county of Plymouth and State ofMassachusetts, have invented certain new and useful Improvements inAutomatic Gunnery-Corrrwting Devices, of which the following is aspecification.

This invention relates improvements in ,devices for giving thenecessary.corrections in artillery firing; and the object of theinvention is to provide a device of the class described which shall givewith greater speed and facility and with less liability to error thenecessary gunnery corrections for use in artillery firing (especiallyWith heavy scacoast guns) than any device heretofore known and whichshall interfere in no way with the usual operations of plotting at theplotting board or with working' of the gun itself. ln heavy artilleryfiring, as is well known` the range tables used are computed on thebasis that atmospheric conditions, muzzle velocity of powder, chargeyweight and form of projectile, etc., are all normal or standard. As amajority o( these conditions are seldom fulfilled it follows that;4various corrections must be applied in elevating andsighting the gun. lnaddition the motion of the ship or target must be allowed for.

In the United States Coast Artillery Service the range or actualdistance from gun to `target at any instant is usually corrected for thefollowing conditions or causes,

viz:

l, Wind, or effect of the Wind in shortening or in-v change the heightof the gun about the plane of the targetfand hence in turn affects theelevation to be given to the gun for a given horizontal range.

4; Atmospheric density as determined by readings of the barometer andthermometer. This in turn atl fects therange attained by the projectile.

5. Motion of the target or the increase, or decrease of range during thetime clapsing from the instant the rangeis determined until theprojectile strikes. That is, one must aim to hit a point in the track ofthe ship and ahead of her at which she will arrive at the time theprojectile strikes. The time elapsing fro'm the instant the range isdetermined to the instant the shot strikes and is evidently made up oftwo periods: (a) The prediction interval, or interval from the instantthe range is determined to the instant the gun is discharged. lThisinterval is usually a constant one and covers the time consumed i'nplotting and determination of the various corrections, time oftransmission o intelligence, setting of gun, etc.; (b) the time offlight of the projectile, a well known interval, which for. anyparticular gun, powder charge, etc., varies with the range. B'asod on aknown change of range for any particular interval,` vsay twenty seconds,it is obvious that the range corrections to be applied would be found bysolving a simple proportion for a number of seconds equal to sum ofprodiction interval and time of flight. y

6. An arbitrary correction may be applied dependent on the rangeattained by the previous shot or shots.

While the above are the usual corrections applied in heavy artilleryfiring, my devices can be readily adapted to make any other rangecorrections or a less number, as may be desired.

The various range effects described above could be allowed or correctedfor by making suitable changes or corrections in the elevation of thegun as given in range tables for lhe particular range considered. lt iscustomary, however, to estimate the effect on the range of the shot of acertain cause and apply the correction to the range. Thus it at 5000yards the effec: of a cer tain wind is to shorten the range by 50 yardsthe practical method is to add 50 yards to the actual distance.

of 5000 yards, thus giving a working range of 5050 on which theelevation is based. Similarly with the other causes noted above. Thus ifa certain cause tends to shorten the range attained by the projectilethe correction is an additional one and viceversa. These effects maybeoither positive or negative, positive when an increase of rangeresults and negative in case of a de crease. The corrections to beapplied obviously are of the opposite sign. Supposing in case of a givenrange, all the various range corrections, each taken with its propersignyare applied to the distance of the target or range. The result is afictitious or working range on which the angular elevation of the gun isbased an( is commonly called the corrected range.y

The objectJ of this device is to give quickljr and mecha-nically thecorrected range. It may also, as will appear hereafter, be used withequal facility to attain the correction to be applied, t', e. thealgebraic sum of thc various corrections. This is a matter ot' detailand depends on the particular system of lire adopted.l

The device for making range corrections is independent of the particularsystem of lire adopted and may be used with a plotting board oranydeviceor devices which give at regular intervals, say every fifteen, twenty,or thirty seconds, (called the observation interval the following data,viz: l. Range or distance of target from gun at any particular instant.during the previous observation interval. 'lhese data are found by wellknown menus which need not be described here. \\'hen arranged lo givethe total cor- 2, (,hange of range rected range this rangewouldobviously be communicatedfjlirect to the gun. When arranged to give thecorrer-.Stien only such correction would beapplied tothe range 'by wellknown methods'.

'This device can similarlybe applied to finding the sight setting orazimuth setting to be given the gun. The corrections usuallyapplied in ahorizontal plane, due to the errors oi deviation are those due to thetollowing causes, viz: 1. Wind, or effect of the wind in vcausing theprojectile to depart to the right or left of the planeet fire. 2'.Drift, or the well known' effect of the` in' causing the proectile todepart from the plane of fire. 3. Travel, or"tlie effect of the motiono'l the y' of Hight only. This since a condition of aiming requites theindex or vertical'wire of the sight to be on the target at the instantof stings The setting' ofl said index would include-the lallowance fortravel. ut in oase In, totalled, of oie U. s. Artillery corps PostamtFinding System where the direction of pointing is set on an azimuthcircle on the gub carriage, and the ele vation by an elevation scaleattached to said carriage it is obvious-that the correction must includea correction for the motion of the ship during the prediction intervalplus the time of flight precisely as in the case of the'- range devicepreviously described.

As shown later this device is adapted either to Case Il or Case 1H. Itis obvious that to secure the corrected range for .the ,variousr heavycoast defense guns,

under any and all conditions by computation it must necessarily lead togreat liability to. costly errors especially when this work must beperformed by enlisted mon of no technical education as is generally thecase. Evidently therefore it is desirable that some device should beprovided -by which the corrected range may he secured without zthisliability of error and by which a hon-technical man" or one with littleeducation may \mechanicallyhiake the' various corrections necessary toinsure theyaccuracy'of eachshot fired from the gun. To provide such adevice is the purpose oi the present invention which is fullyillustrated in the accompanyingorawin'gsin which Figure 1 represents oneembodiment of"y the invention adapted primaiily iorsuse in obtainingcorrected ranges.- 2 represents'a partial elevation of the same drawn toan :enlarged scale with the adding or 'computing device shown insection. Fig. 3 represents a transverse 'section of same en l'ine 3`3 onFig. 2. Fig.

4 represents'a transverse section of the same on linel 4 4 on' Fig. 2.Fig. `5 represents a transverse section through the reading scale, itsgrooved supporting membei,v and index plate, lon line 3-3 on Fig. 2,drawn to I a yet larger scale. 6 represents the reverse of anat'mcisphereY scale -sho'win'g a subtractive graduation thereon, drawnto an enlarged scale. Fig. 7 represents a twenty'jsecond observationinterval scale, enlarged. Fig. Srepresehtsan enlarged elevation of thereading scale and the adding or computing device therefor, the.

various members of which are in their normal or central position. Figs.9 `and 10 represent respectively enlarged sections on 4lines 9.-.9 and10-l0, on Fig. 1, and Figs. 11 and 12 represent respectively anelevation and section of a modified form of adding or computing device.

Similar characters designate like parts thrpughout the-several figuresot the drawings. i

1n th'e drawings, lrepresents a suitable backboard in which is secured aplurality ot' studs 11 on each of which is mounted a'revoluble groovedroller 12. The rollers 12 support a tongue 13 forming with a head 14 asuitable-'1' square which is adapted 'lor movement 1011-' lgitudinallyof said tongue between the rollers 12. The

tongue 13 is provided with a groove 15 longitudinally thereof in whichis mounted a slidable member 16.... The member 16 consists of al bar 17`having secured .to v .either face thereof a scale 18 or 19 the scale 18on one side being graduated in yards of range to acertain point whiletheggraduations are continued upon the other s'cale 19 together with asuitable overlap of the ranges. It is obvious from an inspection of Fig.4that this member 16 be readilyy withdrawn' from thev groove 15 and bereturned therein inreversed position with the scale 19 facing outwardlyoit may beremoved entirely and another member with different rangevgraduations thereon substituted for it. This construction oi thereversible scale dispenses with the' necessity of having too long atongue 13 which would otherwise be required. A plate 20 is hinged at 21t`0 the upper portion of the tongue 13 and t'o the iront face of thisplate 20 is securedan index plate 22 byl means of the screw 23lextendingthrough slots 24 therein, thesel slots providing a ready means forsecuring accurate adjustment of said index plate longitudinally ot' thetongue 13.

Below the tongue 13 is moiinted a member 25 `pi'ovided with an index`26adapted to register with'the graduations on the reading range scale '18and having thereina window 27 through which the operator may read the'scale 28 formed upon the lower outerI face of the tongue 13. The member25 is provided with a second index pointer 29 adapted to register withthe graduations of the scale 28 as it is moved longitudinally thereof.'The origin' or" this scale is 2000l and reads in either direction for500'yards and is adapted for use in connection with the gun arm of anysuitable plotting device.

The member 25 is provided on its under face with a suitable nut 30 towhich is threaded a screw 31 provided with an operating he'ad 32 andhaving bearings 33 in a member 34. It is obvious that by turning thehead 32 the screw 31 will operate upon the' nut 30 to move the member 25longitudinally of the member v34 in either direction thereby causing theindex 35 thereon to register with the graduations formed upontheadjacent edge of the front face ot the rectangular box member 34. f

' The graduations 36 on theV member 34 are for the .purpose ofcorrecting for wind'and are spaced in any predetermined manneradaptedvfor use in any desired system whereby a movement of the index 35to any given graduation on the wind scale 36 would make the desiredcorrection for wind on the reading range scale 130,

18. For convenienceithe origin of the graduations oi the wir/l scale islliven as 300 but any other number might as well be assumed provided itagrebd with other systems with which the device might be used.'

To the bottom of the member 34 is secured a nut 37 to which is threadeda screw 38 provided with an operating head 39 and mountedi\in' hearingsin a similar rectangular' box member' 40. t'lo the front i'aee ol themember 4() is detachably secured a scale 4l provided with arbitrarymarkings thereon adapted to correct for a given tide for the variousranges.

The scale 41 is provided with suitable slots engaged by clamping screws42 which retain said scale in position and which may be operated torelease the scale and allow it to be reversed or another scale insertedin its place. It is obvious that various scales must be used eachhaving' its predetermined arbitrary markings thereon for makingcorrections for tides oi' different heights and for different types oiguns. In the same manner other rectangular box members 43-44 are locatedbeneath the members 34-40 and are similarly moved lengthwise of oneanother by means oi the operating heads 45-46 of the screws 47-48threaded to nuts extending downwardly from the bottom of the members 40and 43. The member 43 is provided with 'means of attachingthereto anatmosphere correction scale, said scale being provided with suitablearbitrary graduations which have been predetermined and are adapted tomake corrections for a given atmosphere, the scale shown in Fig. l beingadapted to make corrections for a l2 atmosphere which is an additiveCorrection.'

' The atmospheric origin isl6 and all corrections for atmospheres above16 are subtraetive corrections and in this case the arbitrary markingswill be `upon the Aopposite side of the center as indicated on the scaleshown in Fig. 6. The index 5]. on the member 40 registers with thearbitrary markings on the atmosphere scale and the member 43 to whichthe atmosphere scale is secured is provided with an index 52 whichregisters with the arbitrary markings for the powder scale 53,detachably secured to the member 44. vIt is obvious that for differentmuzzle velocities and different types ofl guns various scales must beused and for this reason the scales are made4 readily detachable so thata new scale for a new muzzle velocity may be attached conveniently.

The member 44 is operated by means of the screw 54 having bearings inthe lower rectangular box member 55 and provided with an operating head56 by which the member 44 may be adjusted longitudinally thereof so thatthe index 57 upon said member 44 may be moved lengthwise of thecorrection scale 58'by the screw 54 to add' or subtract any arbitrarynumber of yards to the previous range given. This scale 58 ispermanently secured to the backboa-rd l0 byy means o bolts 59, with thezero of said scale in the axis x. y., see Fig. 8, While the indexes of,the various movable members 253440-43, and 44 are all in this axis whenin their normal positions. v

It is obvious from an inspection of the drawings that each of therectangular box membersv 25-34-40-43 44 may be moved independentlylongitudinallyoi the member beneath to makeariy subtractive or additivecorrection while the movement o'f any member will `ried since the lastreading.

carry with it all the members mounted th creon without disturbing anyother settings and the sum of the various corrections thus n'iade willbe indicated. by means of the index 26 lupon' the reading range scale 18thereby automatically and mechanically giving the corrected range to beused at the gun. It is also obvious that where the conditions of eitherone of these causes is constant it is unnecessary to make any changes inthat particular member, the only operation necessary being a change forany cause which has valt is also evident that this device at all 'timesshows clearly what correction has been made and whether any correctionhas or has not been made, this varying from other devices for similarpurposes in use in which one or more corrections may be made andl noindication be shown. as to whether this has been accomplished or not.This uncertainty often requires that the entire operation should berecommenced,'while when the failure to make any desired correction isnot discovered in time, costlyerrors creep into the calculations whichare entirelyl obviated bythe present device. Again it is entirelyimmaterial which correction is made first, or in what order the variouscorrections are made. As the changes for tide, atmosphere, and muzzlevelocity usually remain practically the same lor a considerable periodfor any`particular day the proper scales to be used for the particulartide, atmosphere, and powder, will be placed in position at thecommencement of operations and these only will be exposed to v iew thuspreventing the operator from being confused on mistaking other scalesfor different conditions of tide, atmosphere, and powder as in the caseof other devices new in use. A great advantage accrues from having thesedetachable scales graduated in ranges rather than yards as all thatisnecessary to secure the proper correr-tions for these various causesis toset. the properindex to the mark designating the range given by theobserver ,or otherwise obtained.y v v While the box members25-34---4Q----43---44 are shown as adjustable longitudinally by means olscrews mounted in bearings and threaded to units on the membersimmediately above said screws, it is periectly obvious that any othersuitable means may be used which will permit one member heilig movedlongitudinally of the other and then clamped insaid adjusted position.Figs. ll and l2 in which each member has an upwardly extending rib 60entering a groove in the member next above, which .member is adapted tobe moved on said rib and clamped in adjusted position by the set screw6l. d

The arbitrary correction scale 58'is only used after a shot has beenfired from the gun and found upon plotting to have fallen over or short,as for instance, ii it fell l0() yards short, to correct lor the lastshot, 100 yards would. be added, this being accomplished bya movement oithe index 57 along the scale 58 until it reads 100 yards more It' theshot plotted 200 yards over, then a correction or' 200 yards less wouldbe required and the index 57 moved to the 200 on the left of zero,thereby making the proper correction.

It is obvious from the foregoing and from an inspection of the drawingsthat whatever corrections arc made by means of this arbitrary correctionscale or llO One such modification is shown in any of the movable scalessuperimposed thereon for thel purpose of making corrections of powder,atmosphere, tide, or wind, the algebraic sum of the correctionsw'ill lbe indicated upon the range scale 18'by the index 26 where it may bereadily used and transmitted to the guns as the corrected range to beused, this range scale previously having been moved in the groove luntil the given range, say 7000, registers with the index 22.

l travel of the targets during the time of flight and the` with 7000 asa given range the proper indexes on the movable box members mustregister with the 7 mark on the tide, atmosphere, and powder-scales. Aglance by the range officer at the device would immediately disclose tosuch officer whether or not these different members were properly set.As shown in Fig. l the corrected range for the corrections made from thevarious-causes provided for is 7,130, this read ing being obtained fromthe scale 18 which shows the 'prediction interval.l It must be assumedthat the automatic computing device has corrected for the various causesheretofore mentioned and that the corrected range which for thesecauses, isfas for instance, iri.this particular case 7 ,130, is nowfixed. Hence, if we know l by any means the 'travel correction ofthetarget during the prediction interval and time of flight would be plus200 yards, i. e. the target would move '200 yards further away from thegun before the projectile struck, it is obvious that the actualcorrected range for the target moving at this speed away from the gunsmust necessarily be 7,130 plus 200 yards, making a total corrected rangeof 7,330, which should be the rangesent f to the gunners. In order toprovide for this and secure corrected data for the travel of a targetduring this pre1 diction interval and time of flight the head 14 of theT square is provided with a guide 62 yat right angles to the tongue 13.-On this guide-62 is mounted a tram! mel 63 having a clamp screw 64 bywhich said trammel may be clamped in any adjusted position. The tram-Inel is provided with a downwardly projecting pin 65 (see Fig.. 9)entering a slot 66 in an arm 67 pivoted at 68 to a' plate 69 secured tothe front of the range board 10. Thivarm 67 is adapted to be moved aboutthe pivot 68 by hieans of a handle 70. 1n a suitable groove on said arm67 is slidably mounted a time of flight scale 71- provided with an index72 and a plurality of range graduations 73 with which the index 74 onsaid trammel is adapted to register.V The index.72 is adapted toregister with graduations forming a prediction interval scale 75extending lengthwise of said pivoted arm 67. l'letacliably secured tothe front of the backboard l0 is a travel in observation interval scale76 held in position by means ofsuitalole set screws 77. Several of thesescales are provided for various 'observation intervals and any one ofthese scales may be selected for use as, for instance, 10, l5, 20, or 30lsecond-s. j I

The scale shown in Fig. 1 is for an observation interseam? v val offifteen seconds while the scale 78 shown enlarged in Fig. 7' is for anobservation interval of twenty seconds. Each includes only so much ofthescal-e as would correspond to a speed of twenty-five miles per hourfor a target moving directly to or from the gun. Thus on fifteen secondsscale an extreme .travel of 200 yards is shown inasmuch as a vesselgoing it the extreme speed of twenty-five miles an h our wouldpractically go over 12 yards in one second and in fifteenl secondsfifteen times that, or only 180 yards, showing conclusively that withthe extreme speed of the figlessel for a fifteen-seconds interval only200 yards are needed in extreme cases. The other travel and observationinterval scales are similarly proportioned. vmIt isl obvious that if thearm 67 is moved about its pivot to the 20G-yard mark uponv the traveland observation interval scale the tongue 13 of the T square beingconstrained to move in a direct line upon the rollers l2 will be movedinto the position shown lin dotted lines v upon Fig. 1 and cause a newreading' upon the range scale, this being the total corrected range to'be sent to the gun. Before the arm 67 is swung into this position theindex 72 must register'with the prediction interval used andthe trammel63 moved so that its index 74 registers with thegi'ven range, i'. e.7000. The time of flight scales are interchangeable and other 'similarscales for different muzzle velocities or different types of guns may beinserted inlieu of theorie shown in the drawings. The travelinobservation interval-scale is entirely independent from the predictioninterval scale so that the'observations may he continued vat statedintervals irrespective of the time of firing of Vthe gun. This is agreat advantage as observations may be taken at different and shorterintervals than the prediction intervals and as a consequence tlie variavtions of speed and travel of the target may be observed and used morenearly at the time of firingy of the gun.- By this means changes inspeed can be more accurately ascertained at the time of firing than inthe case where the last observation has to be taken. lt is obvious thatthis same boardmay be used for different cal'ibers of guns by changingthe time of flight and the various .letachable scales on the autom: 4iccomputing device `for others prepared for another type of gun as forinstance 12 B. L. R.

1n the operation o the device the range oliicer or chief plotter at thebeginning of practice determines the condition for the day-powder,atmosphere, tide,

etc., and places on the box members 40-43-44 the corresponding scales.The time of `flight scale 67-is now set to the predetermined predictioninterval and' the proper observation interval scale attached to thebackboard. The observer at the range finder observes -the position ofthe target and transmits 'the range and the range from the gun to thetarget is found bythe plotting detail lwhich in the present examplewill' be assumed to be 7000 yards. Proper ticle, atmosphere, and powderscales having been placed in position upon their respective box membersthe operator manipulates the screw heads 39-45-46 to adjust the tide,atmosphere and powder indexes to the arbitrary markings fcV r'OOO-yardrange. The index 741 i is set at 7000-yard .ange and the wind index is set for any reading which may be given by any suitable wind device.

'26 on the range sca-le i8. This corrected range goes direct to the gun`The distance to last plotted position ol' the target is now called offand all operations 'continue as before, everything now being ready fortravel on the next observation. One throwv of the arm (i7 thus solvesthe proportional travel and at the same time adds it into the range aspreviously corrected giving total corrected range. By this means titecorrected range is held and travel determined by last observationinterval is quickly added in to give the total. Y v' lt.- is believedthat from the foregoing the operation will be hilly understood Withoutany further descrip tion. lhe construction and operation of the deviceis so simple that enlisted men of ordinary intelligence may be readilytaught the principles o the device and operate it effectively as tooperate this device requires no knowledge of gunnery.

In many other devices utilized for this purpose the computations are somany and the operations are so complicated that only trained men arecapable oi operating the same and as these trained men are often scarceit is a great advantage to have a device which may be readily operatedby the majority Vol the members of a coast artillery organization.Moreover, another ad vantage ol the present device is the absence ol'curves, strings, and charts, which are liable to easily get out oi orderand be al'iected by the changes in the weather conditions. 'lhe presentdevice is iree from all ot these objections, all ol' the parts beingmechanically constructed and united in such a manner as to makeeach'act'ion positive and accurate.

Where the Wind, tide. atmosphere, and powder and other arbitrarycorrections remain constant as is olten the case all the corrections forthese conditions including the travel may be made by one motion of thelever (57 which obviously is a great advantage. Another great advantagein this device is that the travel is determined on the observed travelin the last observation interval instead ol' as usual in the onepreceding. Any changes ollspeed are therefore more closely iollowed. lt`is only necessary in the use ol tht present device for an expert, thatis the range oiiicer or chiel' plotter, to determine the conditions atthe beginning 0i practice and adjust the scales. ln this device onlyactual v conditions are exposed thereby minimizing 'errors bytheeliinination ol` all scales not in actual use.

The provision ol' fedex ice ol this nature whereby the predictioninterval may be changed at will and in which any desirel interval may beused is a great advantage. and this is also true ol the ability tofreely change the device so that any observation interval I may be used.Moreoverl anothei advantage in this connection is the entireindependence of the observation interval from the predictionintervals/hereby there is nonecessity ol the intervals being the sameand an Vopportunity is afforded of changing either of these intervalsaccordingfto the degree of efficiency of the personneloperatingfupthedifferent devices. ',-For` instance With rapid trainedplotters it might be possi ble to take two observations during oneprediction interval.

The apparatus has been more particularly described to make variouscorrections for different causes and register the same upon the rangescale 18 from which may be read the total corrected range to be sent tothe gun for use in aiming or laying. 'lhe apparatus'is equally welladapted to indicate by means ol the scale 28 upon the tongue i3 thealgebraic sum o thetotal corrections to be made, the index 29registering with said scale 28 to indicate thereon the exact algebraicsnm of the total corrections to be applied on the gun arm of a plottingboard or to be used in any other comptitations in connection with othersystems which may be in use.

It is obviously an advantage to have provision made in a singleapparatus whereby the total corrected range may be indicated to be sentdirectly to the gun or the total sum of the various correctionsindicated which may be used in connection with other systems for aimingand laying.

While the device-herein shown is adapted primarily ior usel as a rangeboard lor the purpose ol securing either the algebraic sum oi the' totalcorrections to be used or the total corrected range to be sent to thegun it is obvious that by slight changes ol some oi the scalesthe`device is equally applicable to be used for a deflection board tomake corrections in deviation to the right or leit of the target, .-^e.giving the total sight setting in any adopted system which may be usedor to give thc total corrected azimuth setting by which. the gun is tobe laid.

Claims.

l. '.lhe combination of an arm adapted to he moved about a center; meansb r which the movement; of said arm may be regulated to anypredetermined point; a mov able scale pivotcd lo said arm and slidablein a'tixed path at right angles lo the normal position ot said arm; andan automatic computingr device independent ol said scale buteoperatini:r therewith to make various gtlnnery corrections and indicateVupon said scale the actual corrected data to be used in aiming andlaying.

2.' 'l'he combination of an .arm adapted to be moved about al center; ascale. pivoted thereto and Amovable thereby in n fixed path at.' rightanglesl to the normal position ol said arm; :1nd an automatic computingdevice iinlependent, of but 'coperating with said scale to make variousgunnery corrections and indicate upon said scale the actual correcteddata to be used in aiming,r land laying.

il. 'lhe combination of an arm adapted to be moved about a center; aiixed scale by which the movement of said arm ma \y be regulated; ascale pivoted to said arm movable .in a.ixed path ati right anglesto'thc normal position ol said arm; and an automatic computingr deviceindependent ot' but coiiperaling with said scale and adapt ed to makevarious gunnerycorrections and indicate upon said scale. theactunlcorrectcd data to be used in aiming and laying.

4. 'lhe combination of an arm adapted to be moved about a center; ascale movable in :i fixed path at right angles to the normal position olsaid arm; means interposed hetween said scale and arm t'or varying Athemovement of the scale by the movement of said arm: and an automaticcomputing device independent of but coperating with said scale to makevarious gunnery corrections und indicate upon said scale the actualcorrected data to be used in aiming and laying.

The combination of an arm adapted to be moved about a center; a scalemovableln a fixed path at righty anglesto the normal position ofsaidarm; 'a connector between said scale and arm: and an automaticcomputing deviceindependent of but coperating with said scale to makevarious gunnery corrections and indicate upon said scale the actualcorrected-datato be used in aiming and laying. i I

'6. The combination 'of an arm adapted :to be moved about a center; ascale movable in a fixed path at right angles to-the normal position ofsaid arm; an adjustable connector between said scale and arm adapted tovary the movement of said scale; and an automatic computing deviceindependent ot' butv cooperating with said scale -to make variousgunnery corrections and indicate upon l said scale the actual correcteddata to be used infaiming I and laying.

7. The combination ofan arm vadapted to be moved about a center; ascale/movable in a fixed path at right angles to the normal position ofsaid arm: means 'by which the moveinent oflsaid arm may be regulated toany predetermined point; an adjustable connector between said scale andarm adapted to vary the amount of move ment of said scale by themovement of said arm; and an automatic computing device coperating withsaid scaleA pendent of but coperating with said scalel to make variousgunneryV corrections and indicate upon said scale the actual correcteddata to be used in aiming and laying.

i). The combination of an arm adapted to be moved about a center; meansby which the movement of said arm may bev regulated to any predeterminedpoint; a scale Vmovable in a fixed path at right angles to the normalposition of said arm; a connector between said sleale' and arm; meansfor moving said connector to and from said center to vary the movementof' said scale; and an automatic computingr device cooperating with saidscale to make various gunnery corrections and indicate upon said scaletbe actual corrected data to be used in aiming and laying,

10'. The combination of an arm adapted to be moved about a center; aplurality of graduations thereon; a scale movable in a fixed path atright angles to the normal position' of said arm: a connector `betweensaid scale and arm adapted to be adjusted to register witb`auypredetermined graduation on said arm; and an automatic com\ putingdevice coperating with-said scaleto make various gunnery correctionsandindicate upon said scale the actual corrected data to be used in aimingand laying.

11. The combination of au arm adapted to be moved about a center; aninterchangeable member thereon provided with a plurality ot graduations;a scale movable in a'tixed path at right angles to .the normal positionof said arm; .a connector between said scale and arm adapted tobc'adjusted to register with any predetermined graduation ,on saidmember; and an automatic computing device coperating with said scale ,to'make -various gunnery corrections and .indicate upon said scale theactual corrected data to be used in aiming and laying.

12. The combination of an arm adapted to be moved about a center andprovided with alongi`tudinal groove;

' an interchangeable scale slidable vin said groove; a scale movable ina fixed path at right angles Ato the normal position of said arm: aconnector between said scale and arm adapted to be adjusted to registerany predetermined graduatons on said scale; and an automatic. computingdevice cooperating with said scale to make various gunnei-y correctionsand indicate upon said scale the actual corrected data to be used inaiming and laying.

13. 'llie combination of un arm adapted to be moved about a center; agraduated member slidable thereon; a

lixedpscale adapted to locate the position of said graduated member; aVscale movable in a fixed-path at right angles .to the normal positionofsaid arm; a connector between said vscale and arm adapted to beadjusted-to register with any lerating 4and laying. n i

,prediction an automatic computing device independent of but coptlonsand indicate upon said scale the actual corrected data to be used inaiming and laying. v

14. The combination of an arm adapted to be, moved about a center; atime of fiight scale thereon a scale movable'in a iixed path at rightangles to the normal position of-said arm; a connector between saidscale and armadapted to be adjusted to register with any given range onsaid time tlight scale; and anlautomatic computing device cooperatingwith said scale t'o. make various gunnery corrections and indicate uponsaid scale the/actual corrected data to be used in aiming and laying.

15. The combination of anarm adapted to be moved about, a center; aninterchangeable time of `flight'rscale thereon; a scale movable in afixed lilith at right angles to the .normal position of said arm; aconnector between' said scale and arm adapted to be adjusted. toregister with any given range on said time ot' iiight scale; and anautomatic 'predetermined graduations onsald slidablefmember; and

with said scale to make various gunnery correc- K computing deviceindependent of but coperating with said angles to tbe normal positionoi' said arm; a connector be tween said scale and arm adapted to beadjusted` toiregister any given range on said time of iiight scale; anda'n automatic computing device cooperating with .said scale tomakevariousgunnery corrections and indicate upon said scale the actualcorrected data to be used in aiming 17. The combination of an armadapted to be moved about a center', a` time of fiight scaleslidable`thereon; a

movable in a iixed path at right angles to-tbe normal position of saidarm; a connector between said scaleand arm adapted to be adjusted toregister with any given range on said time of flight scale; and anautomatic computing device coperating.l with said scale to make various4gunner-y interval scale registering therewith; a scale corrections'andindicate upon said scale`the,(actual corrected data to be used in aimingand laying.

18. 'lhe combination of an arm adapted to be moved about a center; amember pivotally connected thereto andy movable thereby in a fixed pathat right angles Ato the normal position of said arm; a scale movablymounted `upon said member; and an automatic computing device independentof but coperatingiwith said scale to make various gunnei'y correctionsand indicate 'upon said scale the actual"y corrected. data to be used inaiming and laying.

19L The combination of an arm adapted to be moved about a center; amember pivotally conn'eted thereto and movable thereby in a xed path atright angles to the normal position of said arm; a reversible scaleInova-bly 'device independent of but coperht'i g with said scale to`make various gunnery corrections and indicate upon said scale theactual'corrected data tobe used in aiming and laying. I

21. The combination of an arm adapted to be moved about a center; amember movable in a fixed path at right angles to the normal' positionof said arm; a scale slidably mounted thereon; a time of flight scale onsaid larm; a* connector between said movable member and said armmovableto register with any 'given range on 4,said time of flight scale;and an automatic 'computing device independent 'of but coperating withsaid scale to make various gunnery corrections and indicate upon saidscale the actual corrected datato be` used in aimng'and laying.

3S. 'lhc combination with a movable member provided with a longitudinalgroove; a .scale slidable in said groove; a. member movable relative tosaid ,rooved member provide'l with two indexes one ot' which is adaptedt) register with said scale: a member parallel thereto provided with aplurality ot' eraduations with which the other index is adapted toroe'ister and also with another index; means for adjusting pne ot saidmembers lengthwise of' the other: a third member parallel to thc others;a correctionscale: and meansflu' removably attaching' said scale to saidthird' member whereby the index on the second memher may registertherewith means for adjusting one of the last-mentioned members relativeto the other whereby variens grunuery corrections may he matig andindicate upon said slidable scale. the actual corrected data to be usedin aiming and-laying.

3). The combination of a'n arm adapted to be moved about a eenter;` ascale indicating; inter 'als of travel by which the movement of said armmay be regulated `a movable scale. pivoted to said arm movable in afixed path at. right angles to the normal position of said arm; and anautomatic computini: device independent of but coiipo'r t.- im, withsaid scale to make various gunuery corrections and indicate up =n saidscale tite actual corrected data to be used in aiming.;r and laying.

40. 'lhc combination of an arm adaptedl to be moved about a center; atime of flight scale thereon; a prediction interval scale by whichto'set said time of flight scale; a movable scale; a connector'. betweensaid scale and arm adapted to be adjusted to register with any givenrange on said time of flight scale; and au automatic computim,y devil-ecnperatint,r with said scale and adapted to make various gunner-ycorrectitms and indicate upon said scale the actual corrected datato beused in aiming and laying.

41. 'lhe combination of an arm adapted to be moved about a conter: :1time of flight scale thereon; a predictionV interval scale ou said armto set said time of flight Scale;-

a travel interval scale by which to set said arm; a movabltl scale aconnector between said scale and arm adapted to be adjusted to registerwith any, given range on said time of flieht. scale; and an automaticcomputing device c(""peratinrr with said scale and adapted to makevarious gunnery corrections and indicate upon said scale the actualcorrected data to .be used in aimim,r and layinf.

42. 'the combination of an arm adapted to he moved about a center.; amember carrying.: two scales adapted for longitudinal movement pivctallyconnected tol'said arm land movable at ria'ht angles to the normalposition of said arm; .md an automatic computing device independent ofbut' cooperating with scales to indicate on one Jche corseazm rectedrange to he used at the gun and on the other the sum of all thecorrections to be applied for various causes.

4?. 'l`he combination of a pendent swinging arm; a handle s curedthereto for moving said arm; a scale pivoted to said arm and movablebetween guides in a horizontal path; and an automatic computing,r deviceindependent 0f but cooperating with said scale to makevarious gunnerycorrections and indicate upon said scale the actual correctcd data to beused lin 'aiming and laying said device, consisting of a plurality ofscaled members parallel with said scale and adapted for longitudinalmovement relative to each other.

4t. 'llie combination of a pendent swinging arm; a handle securedthereto for to said arm and movable between guides; another scaleslid-able longitudinally of said first mentioned scale; and an automaticcomputingy device independent of but cop eratinq with .said seule tomake various gunnery corrections and indicate upon said scale the actualcorrected data to be used in aiming and laying said device, consistini;lot a pluralitygot' scaled members parallel with said scale and adhptedfor longitudinal movement relative to each other. V 4 45. Thecombination of a pendent swinging arm; a handle secured thereto tormoving said arm a member pivoted to said arm and movable between guides;a scale slidahle longitudinally of said member; and an automaticcomputing device independent of but coperating with said scale to makevarious eunnery corrections and' indicate upon said scale the actualcorrected data to be used in aiming and laying said device, consistingof a plurality of scaled members parallel with said scale and adaptedfor longitudinal movement relative to each other.

46. 'lhe combination of a frame; a scale normally fixed thereon; acomputing device consisting of a plurality of scales parallel to eachother and'to said fixed scale, adjustable relative to each other tosecure various readings and rela tive to said fixed scale for colneetingfor too great or too short a range; anda slidable scale mounted uponsaid frame coiperatiny.'I with \the side of said computing devicefurthest removed from said tixed scale and adapted to indicate thereonthe vactual corrected data to'be used in aimingr and laying the gun. Al,

Signed by me at Ioston, Massachusetts, this 13th day of August 1906.

ELMER NV. IIUBBARD.

Witnesses y. I

vILuioLD Il. Bnown,

WALTER E. LoMnAun.

